
US Patent No: 4,593,777
Number of patents in Portfolio can not be more than 2000
Drag bit and cutters
Stats
-
Jun 10, 1986
Issued date -
Feb 8, 1984
filing date -
06/578,183
serial no -
Expired
status
Importance
Abstract
A drill bit comprises a bit body having an operating end face. A plurality of self-sharpening cutters are mounted in the bit body and extend through the operating end face. The cutters have cutting faces adapted to engage an earth formation and cut the earth formation to a desired three-dimensional profile. The cutting faces define surfaces have back rake angles which decrease with distance from the profile. The individual cutting faces may be inwardly concave in a plane parallel to the intended direction of motion of the cutter in use. Each of the cutting members has a stud portion disposed in a respective recess in the bit body and defining the inner end of the cutting member, the cutting face being generally adjacent the outer end and having an outer cutting edge. The centerline of the stud portion is rearwardly inclined, from the outer end to the inner end, with respect to the direction of movement in use, taken at the midpoint of the cutting edge, at a first angle from 80.degree. to 30.degree. inclusive. The cutting face is oriented such that the tangent to the cutting face at the midpoint of the cutting edge and in the center plane of the cutting member is disposed at a second angle, for 18.degree. to 75.degree. inclusive, with respect to the centerline of the stud portion.
First Claim
Related Publications
International Classification(s)
- [Classification Symbol]
- [Patents Count]
Cited Art
| Patent Info | (Count) | # Cites | Year |
|---|---|---|---|
|
|
|||
| 4,350,215 Drill bit and method of manufacture | 54 | 1980 | |
|
|
|||
| 4,200,159 Cutter head, drill bit and similar drilling tools | 69 | 1977 | |
|
|
|||
| 4,505,342 Drill bit | 35 | 1982 | |